{"apiVersion":"1.0","identifier":"CVE-2026-74463","description":"In the Linux kernel, the following vulnerability has been resolved: i2c: jz4780: Cache host clock rate at probe to prevent CCF prepare_lock deadlock Fix a severe AB/BA deadlock between the Common Clock Framework (CCF) and the I2C adapter lock, which triggers when an I2C-controlled clock generator client (like the Si5351) is registered or modified under the CCF. During an i2c client clock (generator) frequency change, the CCF acquires its global -prepare_lock- mutex and the driver calls i2c_transfer() to update the client-s chip registers, stalling for the adapter-s I2C bus lock. Concurrently, an independent, parallel transfer on the same bus (e.g., a GPIO expander handling LEDs) can hold the I2C adapter lock. Inside this parallel transfer path, jz4780_i2c_set_speed() calls clk_get_rate() on the host controller-s input clock to calculate bus timings. This call attempts to acquire the blocked CCF -prepare_lock-, creating a circular dependency that freezes the system. The jz4780 host controller clock itself is static and never changes at runtime. However, calling clk_get_rate() inside the active transfer path introduces an unnecessary dependency on the CCF internal locks. Eliminate this synchronous clk_get_rate() call from the active transfer path by caching the static host peripheral clock rate once - inside the private jz4780_i2c structure during jz4780_i2c_probe(). Update jz4780_i2c_set_speed() to use this cached value, safely decoupling active I2C transactions from the CCF internal locks without any risk of stale timings. Assisted-by web based Google AI (pinpointing the bug and writing the message).","publishedAt":"2026-08-15T13:17:50","lastModifiedAt":"2026-08-19T17:21:03","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-74463","cvssScore":null,"cvssVector":"Pending","epssProbability":0.00177,"riskScore":0,"affectedProduct":"Linux kernel","affectedVersions":"unknown","vulnerabilityType":"Kernel","operatingSystems":[],"links":{"self":"https://www.redsauce.net/api/cves/CVE-2026-74463","webPages":{"es":"https://www.redsauce.net/es/cves/CVE-2026-74463","en":"https://www.redsauce.net/en/cves/CVE-2026-74463","fr":"https://www.redsauce.net/fr/cves/CVE-2026-74463","pt":"https://www.redsauce.net/pt/cves/CVE-2026-74463","de":"https://www.redsauce.net/de/cves/CVE-2026-74463","sk":"https://www.redsauce.net/sk/cves/CVE-2026-74463","el":"https://www.redsauce.net/el/cves/CVE-2026-74463"},"source":"https://nvd.nist.gov/vuln/detail/CVE-2026-74463"}}